1. Field of the Invention
The invention relates to an electromagnetically force-compensating weighing appliance with a load scale supported by at least two levers.
2. Prior Art
In weighers of this kind, the loading scale transfers the load to the levers, in which process the distribution to the individual levers depends on the position of the load on the load scale. The shares of the individual levers are then mechanically added by coupling members and fed to a measuring element. This measuring element may be, for example, a current-carrying coil which, in cooperation with a stationary permanent magnet unit, produces a load-proportional counterforce, according to the known principle of electromagnetic force-compensation. This construction entails the disadvantage that the lever ratio of each individual lever must be mechanically set and fixed by change in distance of the moving joints, in order to avoid corner load errors. Besides, the coupling members between the levers for adding the forces limit the accuracy of the weighing appliance, since these coupling members, at load or temperature dependent movements of the individual levers relative to each other in vertical or horizontal direction result in additional forces which adulterate the weighing result.